The illegality of the 12-to-6 downward elbow is one of the most hotly contested items in the Unified Rules of mixed martial arts — a ban that many in the business, and perhaps most, feel is unnecessary.

But the rule is in fact in the books, and it’s the referee’s job to enforce infractions.

Such was the case on Saturday night, when Eddie Alvarez threw an illegal elbow in the second round of his UFC on FOX 30 main event against Dustin Poirier in Calgary, Alberta. Referee Marc Goddard ordered a standup due to the infraction, after which Poirier rebounded and scored a TKO victory.

There was some question about the standup on social media. Among the most vocal of those critics was UFC welterweight Kamaru Usman, a friend of Alvarez’s who went on a profane tirade and declared that he never wanted Goddard to officiate his bout.

This prompted Goddard to take the rare step for a referee of defending his call on social media. Not only did Alvarez throw an illegal elbow, Goddard said, but he also grabbed the fence and illegally put his finger in Poirier’s ear, which added up to a justified restart.

Goddard also said he’d be happy to oblige Usman’s request.

Usman, for his part, ultimately admitted to overreacting to Goddard’s call due to the emotions of watching a friend and former training partner lose.

You can see the Twitter exchange between the two below:

Fuck that referee. I will not fight if that ref is calling my fight. He cost Eddie that fight smfh #UFcCalgary